fsawwa paper and presentation integrated master planning wpb 12012015

FSAWWA Fall Conf. Track Tue 2A Management Tools for Water Utilities of 15 How Integrated Master Planning Helped UV Surface WTP Meet Future Water Needs

How Integrated Master Planning Helped the State’s Largest UV Surface Water

Treatment Plant Meet Their Future Water Needs

Authors: GJ Schers1 PMP, Timothy Smith1 PE, PMP, Scott Kelly2 PE, Poonam Kalkat2 PhD

1 MWH 2 City of West Palm Beach

1. Introduction

The City of west Palm Beach draws its source water from Lake Okeechobee, Grassy Waters Preserve which

is a pristine Everglades wetland area, and available stormwater systems. Using surface water as its source

water makes this utility fairly unique in the South Florida region and requires the water treatment plant

to regularly adjust the process to meet seasonal variations in water quality. Towards this goal, the City of

West Palm Beach has made several priority improvements to their water treatment plant (WTP) in the

past seven years (FWRC article, Dec 2013) [1]. These improvements include replacement of equipment at

the end of its useful life, elimination of gaseous chemicals for staff and public safety, and modification to

the control and electrical systems to provide automated plant operation and reliable power distribution

as well as backup power generation systems for the plant.

The WTP, located in downtown West Palm Beach, has a rated capacity of 47 MGD and utilizes a

conventional treatment process consisting of coagulation, flocculation/sedimentation, filtration over

dual‐media, biological‐active rapid gravity filters, and disinfection with chloramines. Powdered activated

carbon can be added to the raw water intake of the plant. A corrosion inhibitor (poly/orthophosphate

blend) and fluorosilicic acid is added at the mixing metering header just upstream of the Ground Storage

Tanks. See Figure 1 for a simplified process flow diagram of the existing WTP.

Figure 1: Simplified Existing Treatment Plant Process Flow Diagram

The WTP site structures were originally built in 1894 by Henry Flagler with major expansions in the 1920’s,

1960’s, 1990’s and 2010 and is surrounded by residential homes, high‐rise buildings, and businesses.

Figure 2 shows an aerial photograph of the WTP with a depiction of the location and nature of each recent

improvement.


Figure 2: Aerial picture of today’s WTP

In 2013, the City decided to review the technology alternatives to strengthen the pathogen barriers as a

requirement of a 2008 Consent Order with the Palm Beach County Health Department that will be

discussed in more detail later in this article. The implementation of the membrane based alternative in

the Consent Order was projected to require an immediate utility rate increase. The City questioned if

there could be alternatives that would be less costly in terms of capital and operating costs both in the

short and long term and would not require an immediate rate increase. The City also wanted to confirm

that the facility would meet future demands due to an increasing growth rate in the City while also

quantifying replace and refurbishment (R&R) costs over the long term.


Therefore in 2014, the City initiated an integrated master planning approach to identify the present and

future water facility needs of the City. This article outlines the basic components of this integrated master

planning approach as listed below:

Condition assessment and criticality analysis along with vulnerability assessment of existing WTP

assets are outlined in section 2. Deficiencies identified in this process are translated into R&R

needs for the existing WTP.

Evaluation of treatment alternatives to meet the future requirements of the plant are discussed

in Section 3. This includes raw and finished water quality analysis, to verify trends and changes,

assessment of current and potential future regulations, and options to optimize energy and

chemical usage. In addition the assessment evaluates the possibility of relocating the water

treatment system out of the downtown area and to free‐up space for future commercial and

residential development, an option preferred by some City commissioners.

Opinion of probable construction costs for the treatment alternatives considered above are

outlined in section 4 along with a comparison of life cycle cost of ownership.

The following sections follow the same sequence of integrated master planning, as outlined above.

2. Condition Assessment and Criticality Analysis of Existing Assets

The first step for integrated master planning required a comprehensive condition assessment of the

existing WTP assets by visual inspections of assets as well as extensive discussions with Operations and

Maintenance personnel [3]. Equipment performance data was collected and reviewed to detect

deficiencies such as deviations from original manufacturer’s specifications. The data from inspections was

collected and arranged in lists with asset names and codes, photographs, performance data, condition

assessment rating, and repair and replacement cost for each need.

A description of each water plant area assessment is provided below. Additionally, major findings per area

are highlighted and some examples are included in Table 1:

Process Evaluation: Performance of the existing treatment process was reviewed by analyzing historic

water quality data, monthly operating reports, and other operational records and compared with industry

standards and guidelines, including the Florida Administrative Code, the Recommended Standards for

Water Works, Great Lakes, 2012 edition, and MWH Best Practice Design Guides. In addition to the

condition assessment, a criticality analysis and vulnerability assessment was performed. The results of the

process flow rating review of each individual process are depicted in Figure 3 and shows that a number of

processes including sedimentation basins, recarbonation system, washwater recovery basin, thickener,

and calcium oxide (lime) storage do not meet the ultimate capacity of the plant though they meet the

current plant production needs.

Mechanical Evaluation: The condition of the existing mechanical equipment, such as pumps, blowers,

compressors, piping and valves was assessed for visual defects, vibration, noise, wear and tear, and energy

efficiency. The existing hydraulic performance of the pumps was tested by flow and pressure logging and

the results were compared with the original shop drawing performance curves. Inspection for Health and

Safety and Code compliance was also performed. These inspections included the safety showers/eyewash

equipment, ventilation equipment, fire suppression, and plumbing fixtures.


Figure 3: Graphical depiction of flow rating of each individual treatment process

Structural Evaluation: The structural evaluation documented concrete deterioration and rebar corrosion.

Recorded deficiencies included visual evidence of leaks, spalling, delamination, exfoliation, and exposed,

corroded, or deteriorated rebar. This visual inspection was then supplemented by destructive and non‐

destructive testing for the sedimentation basin and filter reinforced concrete structures consisting of in‐

place rebound hammer testing, Ground Penetrating Radar (GPR) concrete scanning, and strength and

laboratory testing of concrete core samples and steel reinforcement samples.

Electrical Evaluation: The electrical and control systems had undergone considerable investments in the

last seven years providing more reliable power supply to and within the site, full capacity backup power,

and a new communications protocol and control system. Therefore the evaluation only focused on motor

control centers, panels, and instrumentation that were not replaced or substituted as part of the past

upgrades.

Architectural Evaluation: Existing buildings were reviewed in terms of building code compliance, life safety

and general condition. Options to hurricane hardening of the Operations Building were assessed and

presented in the documents and flat roof structures were particularly subjected to a detailed review due

to historical leakages.

Examples of observations during the Condition Assessment for each discipline are included in Table 1.

0

10

20

30

40

50

60

70

80

90

100

Rated

Capacity of the Process (MGD)

Total Capacity per Process (all units on)Process Rating per Process (one unit out of…

Current Rating of WTP = 47 MGD


Table 1: Examples of observations during Condition Assessments for each discipline and a typical photograph w/imaging of the structural non‐destructive investigation

Examples of Major Findings of Condition Assessment per Discipline

Mechanical Electrical

South raw water pump No. 27 needs replacement

VFDs on raw water pumps don’t work effectively

Sludge removal system in basins is at the end of

useful life

Isolation gates/valves in settled water flume and

pipes are defective and inoperable

Some filter and site isolation valves are nearing

the end of useful life

MCC for high service pumps is at end of useful life

and parts are not available

Some site PLCs are obsolete

Multiple UPS systems on site; there is a need to

centralize and make resilient

Some remote panels should be provided with a

secondary power feed

Structural Architectural

Sections of shoreline Clear Lake eroded

Signs of concrete deterioration in the filters and

sedimentations basins

Filtered water flume and underground clearwell

show signs of leakage

Operations Building requires hurricane hardening,

particular in the hardware

Flat roofs are leaking in some spots and should be

rehabilitated or replaced

Buildings should be reviewed in terms of life

safety and ADA

Just an example of the

findings of the concrete

non‐destructive testing:

photograph and thermal

imaging at same location at

the expansion joint in the

east sedimentation basin.

The most relevant results from the criticality analysis and vulnerability assessments are presented in Table

2. As an example, this table notes that some of the hydraulic conduits and connections between the

treatment processes are either single pipelines or single reinforced concrete structures and cannot be

taken out of operation for repair and cleaning without a full plant outage. Another example of a factor

effecting criticality is the significant risk of flooding in both the West and East High Service Pump Stations

due to hydraulic conditions, which can affect mechanical and electrical equipment housed in these

buildings.


Table 2: Significant observations during the Criticality Analysis and Vulnerability Assessment

Area Area Name Single Point of Failure/Vulnerability Description Comment

02 Flocculation and

Sedimentation Basin

Single settled water reinforced concrete flume and

isolation gates which are inoperable affecting the use

of the 60" bypass piping

02 Recarbonation

System

Single carbon dioxide dosing skid feeds a single

dosing point in the recarbonation basin/settled water

flume

Use of bypass piping requires

carbon dioxide to be dosed

also in 60" bypass piping

03 Filters

Single filtered water flume and pipeline and

reinforced concrete flume does not appear to be

watertight which could provide a contamination risk

from storm water runoff and groundwater infiltration

This was also documented in

reports during 2008‐2010

period

03 Filters

Filter control panels have no secondary power feed

and Profibus configuration changes in filter area have

not been completed as per agreed plan

04 Transfer Pump

Station

Pump station has a single wet well without options

for sectional isolation

04 Transfer Pump

Station

Due to floor elevation, a failure of the transfer pumps

in the East HSP building presents a flooding risk

affecting transfer and high service pumps and

associated gear

04 Transfer Pump

Station

Single Mixing and Metering header piping, and single

pipeline cross just upstream of the ground storage

tanks

04‐05

High Service Pump

Stations (East and

West)

Due to floor elevation, the West HSP mechanical and

electrical gear can flood when the control valve to

the 1 MG clearwell fails or loses power affecting raw

water and high service pumps and gear

There have been reports of

flooding and near‐misses in

West HSP in the past

05 Ground Storage

Tank

Old 1 MG below grade clearwell does not appear to

be watertight and introduces a risk for contaminants

from storm water runoff and groundwater infiltration

06 Sludge Thickener

Single sludge thickener and sludge pump station

cannot be isolated or taken out of operation/service

for extended periods of time

De‐sludging from

sedimentation basins cannot

be delayed beyond 12 hours

3. Treatment Alternatives to Meet Future Needs

Assessing the condition of the existing plant systems and identifying areas with process capacity

limitations or systems vulnerabilities, provided a baseline for evaluation of upgrades and treatment

alternatives for modernizing the existing plant.

The existing process has been successful in meeting the primary and secondary drinking water standards

and regulations over the last eight years. However, in 2007, a series of bacteriological hits in the

distribution system led to two boil water notifications. Investigations by Public Utilities department staff,

regulators, and consulting engineers led to the discovery of an improperly sealed interconnect not shown

on as‐built drawings, which allowed filtered, chlorinated water to bypass the storage tanks without

providing the contact time necessary for bacteriological and virus kill prior to distribution. Subsequently,


the regulator (the Palm Beach County Department of Health) and the City entered into an agreement

(Consent Order) to upgrade the City’s WTP by 2018.

In addition the Utility wanted to address the concern of always being able to meet both the Stage 1

Disinfection and Disinfection Byproduct (D/DBP) and Long‐Term (2) Enhanced Surface Water Treatment

Rule (ESWTR) requirements, i.e. meeting the Total Organic Carbon (TOC) removal and pathogen log

inactivation requirements, while not exceeding the maximum disinfectant residual level of chloramines

and disinfection byproduct levels of trihalomethanes (THM) and haloacetic acids (HAA). These

requirements are summarized in Table 3.

Table 3: EPA Rules affecting on‐going operation

Rule Contaminant or Treatment

Requirement

Limit

Stage 1 D/DBP Rule: Maximum

Contaminant Levels (MCL)

THM

HAA

80 µg/L

60 µg/L

Stage 1 D/DBP Rule: Maximum Residual

Disinfectant Levels (MRDL)

Chloramine 4 mg/L

Stage 1 D/DBP Rule: Required Removal of

TOC

TOC removal >=40%

Surface Water Treatment Rules (Original,

Interim and Long‐Term)

Virus inactivation

Giardia inactivation

Filtered water turbidity

Cryptosporidium inactivation

4 log

3 log

<0.3 NTU 95%, <1.0 NTU 100%

2 log

While the criticality and vulnerability assessment identified current deficiencies in the water treatment

process and opportunities for improvements, it did not address future regulatory drivers including: final

Contaminant Candidate List 4 (CCL‐4), final Third Determination of CCL‐3, proposed Carcinogenic Volatile

Organic Compound (cVOC), Lead and Copper Rule Long‐Term Revisions (LCR‐LTR) and Perchlorate Rules,

and Third Six‐Year Review.

Following the stipulations in the Consent Order and based on the future regulations mentioned above,

the City determined that the future water treatment process should include additional pathogen

protection and additional taste and odor (T&O) control. The considered processes to provide additional

treatment for pathogens and T&O included activated carbon treatment (either granular or powdered),

anion exchange, low pressure membrane filtration, high‐rate clarification, and ultraviolet light

disinfection. Other processes, while potentially effective for additional treatment as outlined above, were

discarded for a variety of reasons. For example, ozone for T&O control would have resulted in elevated

bromate levels in the finished water, close to or even above the standard of 10 µg/L [5].

A short description of each alternative is provided below, while a more detailed process description and

simplified Process Flow Diagrams (PFD’s) are presented in Figure 4:

Alternative 1: PAC‐UV: Alternative 1 maintains the existing lime softening process with the addition of a

dedicated powdered activated carbon (PAC) contact chamber on the raw water for T&O control.

Additional pathogen protection is provided with ultraviolet (UV) light disinfection process downstream of

the filters.

Alternative 2: IX‐UF‐GAC: Alternative 2 is located on a 4.5‐acre vacant lot on the existing WTP site and

uses new processes in suspended anion exchange (IX), ultrafiltration (UF) membrane treatment, and

granular activated carbon (GAC) absorption. Additional pathogen protection is provided with the


membranes and the extended free chlorine contact time. T&O control is provided with GAC Absorption

through an extended empty bed contact time.

Alternative 3: IX‐UF‐GAC (ECR Site): Alternative 3 is in essence the same process as Alternative 2, however

it is located on a Greenfield site near the East Central Regional (ECR) Water Reclamation Facility (WRF).

Once relocated, the existing WTP site would be redeveloped for residential and/or commercial use.

Additional pathogen protection is provided with membranes and an extended free chlorine contact time.

T&O control is provided with GAC Absorption with an extended empty bed contact time.

Alternative 4: ENH.COAG‐ACT‐UF (Riviera Beach Site): Alternative 4 includes Actiflo‐Carb® and

ultrafiltration membrane treatment, and is located on a new site in Riviera Beach. The existing WTP site

would be redeveloped for residential and/or commercial development. Additional pathogen protection is

provided with the membranes and extended free chlorine contact time. T&O control is provided with

continuous PAC pre‐treatment integrated with the Actiflo® clarification process.

4. Cost of Alternatives and Financing Options

The R&R needs for each treatment alternative are different due to the different approaches towards the

use of existing assets. The plant upgrades needs for each alternative are also different due to the use of

different treatment processes to meet the objectives.

For each alternatives, capital, operating and life cycle cost estimates were prepared, as outlined below.

Capital Cost Estimates for Plant Upgrades

Planning level capital cost estimates (CAPEX) for each alternative were developed. A contingency

allowance of 30% is considered in the cost estimates of which 20% was included in the cost estimate and

the other 10% was allocated by the City in the City’s reserve. The CAPEX estimates follow Class 5 Opinion

of Probable Construction Costs (OPCC) as defined by the Association for the Advancement of Cost

Engineering International (AACEI), Recommended Practice No. 18R‐97. This level of cost is a planning level

order of magnitude cost with an expected accuracy range of ‐20% to ‐50% below and 30% to 100% above.

A summary of the CAPEX is included in Figure 5. The CAPEX for Alternatives 3 and 4 includes the

conveyance to and from the new sites and demolition of structures at the existing WTP, removal and

disposal of construction debris off site, remediation of the drinking water sludge area to prepare the site

for new residential, and commercial construction. It also contains the market value of the 26 acres

property of the existing WTP site, which becomes vacant when a replacement WTP is built and is

operational at a new site. As shown, the onsite alternatives were more cost‐effective than the off‐site

alternatives. Alternative 1 PAC‐UV has the lowest CAPEX at $33.5 million, with Alternative 2 IX‐UF‐GAC (at

existing site) the next most cost‐effective option with an additional CAPEX of $74.2 million. Alternatives 3

and 4 (the off‐site alternatives) are at least $250 million more expensive than Alternative 1. From the off‐

site alternatives, Alternative 4 ACTIFLOCARB‐UF (at Riviera Beach) is more cost‐effective mainly due to

the reduced CAPEX for the raw water and finished water conveyance.


Alternative 1 (at WTP site) PAC improvements involve new auger, slurry mixer and dosing lines to the new PAC basin. Continued use of sedimentation basins will ultimately involve re‐rating by providing additional valving, extending flocculation zone, and providing lamella plate settling units and replacing the sludge removal system. Recarbonation will be provided in settled water flume and settled water pipe. Existing rapid gravity filters (RGF) will be provided with new media. Filter effluent will be combined requiring additional isolation valves and pipelines. A new transfer pump station will be provided to convey flow through the new UV installation to the existing mixing and metering header. The new UV system and associated equipment will be housed in a new building. Finished water will be dosed with free chlorine downstream of the UV system before chloramine formation at the existing mixing and metering header. The existing filtered water flume and buried clearwell will be demolished.

Alternative 2 (at WTP site) A new IX process will be included to remove the organics. UF membranes will be provided for suspended solids and pathogens removal and will be housed in a new building. The membranes will be located downstream of IX, while existing dual media filters will be converted to GAC absorbers by changing the media. The 32 re‐purposed filters will be retrofit with plastic underdrain block with an IMS cap allowing for deeper media depth and covered with retractable FRP covers. Similarly to Alternative 1, effluent from the GAC contactors will be combined and transferred to a new reinforced concrete chlorine contact basin to provide a free chlorine contact time providing virus and Giardia inactivation control. Chloramines will be used as secondary disinfectant. This alternative will involve the excavation of unsuitable soils from the vacant lot and will eliminate existing filtered water flume and buried clearwell.

Alternative 3 (West, near ECR site) The process is an exact match of Alternative 2. UF membranes will be constructed for suspended solids and pathogens removal and will be housed in a new building. New GAC adsorbers will be constructed using pressurized vessels instead of open reinforced concrete structures. Free chlorine will be used for primary disinfection and chloramines for maintaining a residual in the distribution system. This alternative requires the repurpose of the existing vacant 26‐acre site on the south side of Jog road, east of the City well field.

Alternative 4 (East, Riviera Beach site) A new enhanced coagulation process integrated with PAC pretreatment will be provided to remove source water organics and T&O. UF membranes will be constructed for remaining suspended solids and pathogens removal and will be housed in a new building. The membranes are located downstream of the Actiflo® Carb process and safety strainer. A new chlorine contact basin will be constructed to provide free chlorine contact time for virus and Giardia inactivation. Chloramines will be used as a secondary disinfectant. The proposed 8.5‐acre treatment site is west of the FPL power facility in Riviera Beach. Raw water will be pumped approximately 3.75 miles north from the existing WTP site and finished water will be pumped back to existing site.

Figure 4: Simplified diagram and a description of each of the treatment alternatives

50 mgd

Clear Lake

ChlorineAmmonia

CausticFerric Sulfate, Acid

PAC

Actiflo –Carb®Offsite

Storage

Polymer,

Microsand

UF


Figure 5: Graphical depiction of CAPEX for each of the alternatives

Annual Allocation for R&R Needs

The MWH team conducted field inspections and assessments of the existing plant assets as described

before. In addition the team defined the refurbishment and rehabilitation (R&R) needs of the

infrastructure that would need to be maintained as part of the long term solution to upgrade the WTP

with either UV disinfection (Alternative 1) or UF membrane (Alternatives 2‐4) technologies. The two

alternatives at the existing site (Alternatives 1 and 2) have different R&R needs based on the existing

processes and structures remaining in service. Similarly, the offsite alternatives (Alternatives 3 and 4)

require only urgent repairs until the new plant is operational as reflected in the early R&R costs.

CAPEX estimates for R&R needs were developed for the next 10 years (Periods 2015‐2019 and 2020‐2024)

with the same planning level accuracy as the Plant Upgrades CAPEX estimates. The R&R needs for the

following 20 years (Period 2025‐2044) were estimated and included in the assessment for completeness,

and were kept the same between the options. The CAPEX numbers were subsequently amortized to an

annual allocation. The results are presented in Figure 6.

Alternative 1 ‐PAC‐UV

(at existing site)

Alternative 2 ‐IX‐UF‐GAC

(at existing site)

Alternative 3 ‐IX‐UF‐GAC (near ECR)

Alternative 4 ‐Actiflo‐Carb‐UF

(at RivieraBeach)

Other Fees $5.6 $18.0 $61.2 $51.3

Site Property Value $0.0 $0.0 ‐$33.2 ‐$33.2

Site Works, Power, Demolition $4.3 $14.0 $76.7 $69.4

Treatment $23.6 $75.1 $96.1 $92.6

Pump Stations, Storage,Conveyance

$0.0 $0.7 $161.9 $109.2

‐$100

‐$50

$0

$50

$100

$150

$200

$250

$300

$350

$400

$450

2018 CAPEX

Cost

(in M

illions)

Other Fees

Site Property Value

Site Works, Power,DemolitionTreatment

Pump Stations,Storage, Conveyance $33.6

$107.7

$362.7

$289.3


Figure 6: Annual Cost of R&R needs

Operating Cost Estimates

Estimates of Operating Expenses (OPEX) were evaluated on the basis of energy, chemicals, labor,

maintenance and repair, sludge hauling and disposal, liquid waste disposal to sewer and other

miscellaneous items. Energy costs include pumping for primary and secondary flow streams, mixers, lime

slakers, sludge collection, UV power draw, and other electrical consumers at the WTP. Energy costs also

include the conveyance to and from the offsite location for Alternatives 3 and 4. Chemicals include PAC,

IX resin, sodium chloride, unslaked lime, ferric sulfate, sulfuric acid, micro‐sand, cationic polymer, carbon

dioxide, membrane cleaning chemicals, GAC regeneration or replacement, UV cleaning acid, sodium

hypochlorite, aqueous ammonia, sodium hydroxide (or caustic soda), poly/orthophosphate (corrosion

inhibitor), hydrofluorosilicic acid (fluoride), and anionic polymer. Labor costs include burden costs for full‐

time equivalent (FTE) estimates for supervisors, operators, technicians, and administrative assistants

based on requirements of 60‐699.310 F.A.C. Category I or Category II staffing requirements and the 2014

organizational staffing plans for the City’s WTP. Sludge disposal costs include lime sludge or ferric sludge

thickening and dewatering, storage, hauling, and disposal. Sewer disposal costs include disposal of liquid

wastes into the sewer including filter press filtrate, Washwater lamella separator sludge, and ion exchange

waste brine. Miscellaneous operating costs are items not specifically called out above like diesel fuel

usage, hired labor and technicians and other maintenance materials, and calibration chemicals for

instruments. Unit costs for each of the above operating cost categories were obtained from the City or

from vendors. The operating costs for 2018 are summarized in Figure 7.


(at existing site)

Alternative 2 ‐IX‐UF‐GAC

(at existing site)



(at RivieraBeach)

Annual R&R CIP 2015‐2019 $2.8 $2.3 $0.9 $0.9

Annual R&R CIP 2020‐2024 $6.4 $1.7 $0.0 $0.0

Annual R&R CIP 2025‐2044 Est. $4.8 $4.8 $4.8 $4.8

$0.0

$1.0

$2.0

$3.0

$4.0

$5.0

$6.0

$7.0

Annual R&R Costs

(in M

illions)

Annual R&R CIP2015‐2019

Annual R&R CIP2020‐2024

Annual R&R CIP2025‐2044 Est.


Figure 7: Graphical depiction of OPEX for each of the alternatives, compared with the existing situation, for the year 2018 at a flow of 27.5 MGD

The annual OPEX in 2018 for the existing water treatment plant is forecast at approximately $15.2 million.

For Alternative 1 PAC‐UV the annual OPEX is forecast to increase to $15.4 million due to the addition of

PAC and UV treatment and for Alternative 2 IX‐UF‐GAC (at existing site) and Alternative 3 IX‐UF‐GAC (near

ECR) these costs are forecast to reduce to $12.5 and $12.1 million, respectively, mainly due to the

reduction of the use of coagulation chemicals and disposal of sludge. For Alternative 4 ACTIFLOCARB‐UF

(at Riviera Beach) the annual OPEX is forecast to remain the same as the existing water treatment plant.

Life Cycle Cost Estimates

The summary of the life cycle costs estimates, expressed in Net Present Value (NPV), are provided in

Figure 8. The Net Present Value calculations assume an estimated construction completion date in 2018

to meet the Consent Order deadline. The CAPEX of the Plant Upgrades and the annual expenditure of R&R

and the operating costs were presented in the sections before.

NPV costs are forecasted starting in year 2018 to coincide with project completion. The NPV shown for

year 0 represents cumulative expenditures for years 2015 through 2018. The existing WTP NPV includes

2.5 million dollars (2018 $) per year for R&R. CAPEX, R&R and OPEX costs for the existing WTP and

Alternatives 1‐4 are illustrated as stacked graphs in Figure 8. The alternatives utilizing the existing site

(e.g. Alternatives 1 and 2) have a lower NPV than the offsite alternatives (e.g. Alternatives 3 and 4). From

the onsite alternatives, PAC‐UV (Alternative 1) is more cost effective in the first 15 years of operation,

Existing


(at existingsite)

Alternative 2 ‐IX‐UF‐GAC(at existing

site)



(at RivieraBeach)

Other OPEX $3.91 $3.91 $3.91 $3.91 $3.91

Waste to Sewer $0.10 $0.10 $0.20 $0.19 $0.11

Sludge $0.96 $0.96 $0.00 $0.00 $0.90

Labor $4.47 $4.47 $4.19 $3.63 $3.63

Chemicals $4.38 $4.38 $2.22 $2.22 $4.24

Energy $1.40 $1.44 $1.54 $1.70 $1.83

$0.00

$2.00

$4.00

$6.00

$8.00

$10.00

$12.00

$14.00

$16.00

$18.00

2018 OPEX

Cost

(in M

illions)

Other OPEX

Waste toSewerSludge

Labor

Chemicals

Energy


however after year 15, IX‐UF‐GAC (Alternative 2) becomes more cost effective, mainly due to the lower

OPEX. From the off‐site alternatives, ACTIFLO‐CARB‐UF (at Riviera Beach) (Alternative 4) is more cost

effective in the first 22 years of operation but after year 22, IX‐UF‐GAC (near ECR) (Alternative 3) becomes

more cost effective.

Figure 8: Graphical depiction of NPV for each of the alternatives

Financing Options and Impact on Rates

Several financing options were considered for each treatment alternative because of the differences in the initial CAPEX needs. A financial summary is provided in Table 4. The credit rating of the City of West Palm Beach is slightly different for each rating agency, but is general around ‘AA’ (double A). The utility department has already a relatively high debt, translated in the current rate being in the top quadrant of all utilities rates in Florida, compared to the City’s own targets:

Debt outstanding to net plant ratio is 49.6% (target <50%)

Debt per customer is $2,579 (target <$1,800)

Affordability to customers is 2.48% (target of <2.00%)

Based on the existing debt situation not meeting targets, the City expressed an interest to pursue opportunities to look at alternative financing options, if possible and feasible. Such alternative option was considered for alternative 1, with the relatively low initial capital needs. The available funds in the City’s Utility Reserve Fund would suffice to cover the initial CAPEX needs. Alternative financing options were considered but found not feasible for Alternatives 2 and 3, and the capital necessary to fund the CAPEX needs would need to be raised through the issuance of new bonding. Private financing would fund Alternative 4. This option also assumed that the ownership and operations of the new assets would be in

$0

$100

$200

$300

$400

$500

$600

$700

$800

$900

$1,000

0 5 10 15 20 25 30

Cumulative Net Present Value

(2018 M

illions)

Years in Operation

Alternative 1 PAC‐UV(at existing site)

Alternative 2 IX‐UF‐GAC(at existing site)

Alternative 3 IX‐UF‐GAC (near ECR)

Alternative 4 Actiflo‐Carb‐UF(at Riviera Beach)

Existing


private hands under a 30‐year concession agreement between the City and the private company. The financial implications on utility rates for all alternatives were estimated based on current best knowledge of capital needs, financing costs and yearly operations costs.

The Utility Department management brought the results of the study, as presented in Table 4, to a City Commission meeting for decision making. Extensive discussions transpired on details of the alternatives, but in the end the City decided to move forward with Alternative 1 as it would not degrade the Utilities debt position and would not require an immediate utility rate increase. The project team is moving ahead with the design and ground breaking for construction is expected in late spring of 2016.

Table 4: Summary of Financing Options and Parameters for Alternatives

Alternative 1

PAC‐UV (at existing site)

Alternative 2

IX‐UF‐GAC (at existing site)

Alternative 3

IX‐UF‐GAC (near ECR)

Alternative 4

Actiflo‐Carb‐UF‐GAC (at Riviera

Beach)

CAPEX $33.6m $107.7m $362.7m $289.3m

R&R 2015‐2019 $2.8m/yr $2.3m/yr $0.9m/yr $0.9m/yr

Financing option considered for CAPEX and R&R ‘15‐‘19

City’s Utility reserve and book

balance

Utility bonds from market

Utility bonds from market

Private funding through external contract ops

R&R 2020‐2024 $6.4m/yr $1.7m/yr $0.0m/yr $0.0m/yr

Financing option considered for R&R ‘20‐‘24

Pay as you go (from yearly

budget surplus)

Pay as you go (from yearly

budget surplus)

Not applicable Not applicable

Expected immediate increase of utility rate

No increase 3% 35% 23%

Expected annual increase of utility rate (4‐year average) due to R&R needs

2.0% 1.5% 1.0% 1.5%

5. Conclusions

In summary, this integrated master planning approach to the City’s water treatment plant, included an

assessment of the current condition of assets, performance review of process systems and a criticality

and vulnerability assessment. The existing plant asset condition and performance information was linked

with the needs of future treatment improvements to ensure that the true total cost of ownership and

final treatment concepts were considered during project planning and alternatives evaluation. The

presentation of an integrated master planning methodology using a case study for the City of West Palm

Beach may be used by other utilities planning major repairs and improvements to their treatment

facilities. A similar systematic and comprehensive approach can also be helpful in evaluating financing

options, including the potential for using Utility’s Reserve and pay as you go approach to utility upgrades.

In the City of West Palm Beach’s case, once the true cost of ownership was determined, the City was able

to eliminate a planned utility bond issuance, was able to forgo two previous scheduled utility rate

increases, and fund water facility projects through existing and future internally generated funds with no

additional debt to the City.


Literature [1] GJ Schers et al, City of West Palm Beach Makes Priority Improvements to Aging Water Treatment Plant,

published in FWRC 2013

[2] Scott D. Kelly et al, City of West Palm Beach diverse source water system, Paper presented at FSAWWA

2014

[3] MWH WA‐28.1 Task 9.2 Field Inspection and Condition Assessment at the City’s WTP Facilities, Final

Report, July 2014.

{4] MWH (sub: Amec) WA‐28.1 Task 9.2 Concrete Condition Assessment of the City of West Palm Beach

WTP, July 2014.

[5] MWH WA‐28.1 Task 9.3 Capital Investment Program (CIP) for the City’s WTP, Final Report, July 2014.

[6] MWH WA‐31 Task 2 Evaluation of Water Treatment Alternatives, Final Report, January 2015

How Integrated Master Planning Helped the State’s Largest UV Surface Water Treatment Plant Meet Their Future Water Needs

December 1, 2015

Poonam Kalkat, PHDTimothy J. Smith, PE

Overview

• Facility background

• Why an integrated master planning approach?

o Criticality analysis, condition and vulnerability assessments

o Evaluation of treatment alternatives

o Cost alternatives and financing options

• Conclusion

2

3

Facility Background

4

Facility Background

Simplified Existing Treatment Plant Process Flow Diagram

In 2007, a series of bacteriological hits in the distribution system led to boiled water notifications. Subsequently, the regulator and the City entered Consent Order to upgrade the City’s WTP by 2018.

6

Why an integrated master planning approach?

2008 Consent Order• Strengthen the pathogen barriers in

their treatment process

• Membrane technologies original selected to provide this barrier

o Rising costs

o Change in administration

Other Options?• Were there other alternatives that

would achieve the same objective with lower short and long term costs?

• Since a new plant was not necessarily the solution, the existing facilities needed to be evaluated

o Meet future growth needs?

o R&R costs reasonable?

2014, the City initiated an integrated master planning approach consisting of:

• Criticality analysis and condition assessment along with vulnerability assessment of existing WTP assets

• Evaluation of treatment alternatives to meet consent requirement and future requirements of the plant

• Lifecycle cost alternatives and financing options for the various alternatives

7

Why an integrated master planning approach?

Process Evaluation: Performance of the existing treatment process was reviewed by analyzing historic water quality data, monthly operating reports, and other operational records and compared with industry standards and guidelines.

9

Criticality Analysis – Overall Plant Process

Criticality Analysis – Overall Plant Process

Graphical depiction of flow rating of each individual treatment process

10

0

10

20

30

40

50

60

70

80

90

100

Rat

ed C

apac

ity o

f the

Pro

cess

(M

GD

)

Total Capacity per Process (all units on)

Process Rating per Process (one unit out ofoperation)

Current Rating of WTP = 47 MGD

A number of processes did not meet the ultimate capacity of the plant though they meet the current plant production needs.

Criticality Analysis and Condition Assessment of Existing Assets

Analysis and Assessment

• Visual inspections

• Interviews with operations staff

• Collection/Review of equipment performance data

• Existing asset data included:– Asset names/codes

– Age/service life

– Photographs

– Performance data

– Condition assessment rating

– Repair and replacement cost

11

Criticality Analysis and Condition Assessment of Existing Assets

More than 500 assets were analyzed

12

13

Condition Assessment – Mechanical, Structural, and Electrical

Mechanical Evaluation Structural Evaluation Electrical Evaluation

• pumps• blowers • compressors • piping and valves

• concrete deterioration• rebar corrosion• Leaks, spalling, and

delamination• exfoliation

• motor control centers

• panels• instrumentation

Each assessed for visual defects, vibration, noise, wear and tear, and energy efficiency.

Supplemented by destructive and nondestructive testing

The electrical and control systems had undergone considerable investments in the last seven years

Architectural Evaluation: Existing buildings were reviewed in terms of building code compliance, life safety and general condition. Options to hurricane hardening of the Operations Building were assessed and presented in the documents and flat roof structures were particularly subjected to a detailed review due to historical leakages.

14

Condition Assessment – Code compliance and life safety

15

Example of Major finding of Condition Assessment

Mechanical Electrical

South raw water pump No. 27 is failing VFDs on raw water pumps don’t work Sludge removal system in basins at end of life Isolation gates/valves in settled water flume and pipes are

defective and inoperable Some filter and site isolation valves are nearing the end of

useful life

MCC for high service pumps is at end of life and parts are not available

Some site PLCs are obsolete Multiple UPS systems on site; there is a need to centralize and

make resilient Some remote panels should be provided with a secondary power

feed

Structural Architectural

Sections of shoreline Clear Lake eroded Signs of concrete deterioration in the filters and

sedimentations basins Filtered water flume and underground clearwelll are leaking

Operations Building requires hurricane hardening, particular in the hardware

Flat roofs are leaking in some spots and should be rehabilitated or replaced

Buildings should be reviewed in terms of life safety and ADA

Example of the findings of the concrete non‐destructive testing: thermal imaging at the expansion joint in the east sedimentation basin.

Existing plant systems and additional treatment alternatives were evaluated

• To identify process capacity limitations or systems vulnerabilities

• For meeting future regulatory drivers

• Based on consent order requirements, above criteria and feasibility of implementation the following processes were shortlisted:

– Anion exchange

– Low pressure membrane filtration

– High‐rate clarification

– Ultraviolet light disinfection

Being a surface water plant, activated carbon systems (either granular or powdered) were included for Taste and Odor treatment.

17

Basis of Evaluation of Treatment Alternatives

Alternative 1: PAC‐UV

18

Treatment Alternatives – PAC-UV

Existing Lime softening process

PAC-T&O control

UV-Additional pathogen protection

Existing site and processes used

Alternative 2: IX‐UF‐GAC

19

Treatment Alternatives – IX-UF-GAC

IX,UF membrane (Additional pathogen

protection)

CL contact-Additional pathogen protection

GAC-T&O control

New processes built in a vacant section of the existing site

Alternative 3: IX‐UF‐GAC (Offsite)

20

Treatment Alternatives – IX-UF-GAC (offsite)

IX,UF membrane (Additional pathogen

protection)

GAC-T&O control

CL contact-Additional pathogen protection

New site and processes-need underground utilities to and from new site. Option for redeveloping existing site for residential and/or commercial use.

Alternative 4: ENH.COAG‐ACT‐UF (Offsite)

21

Treatment Alternatives – ENH.COAG-ACT-UF (offsite)

50 mgd

Clear Lake

ChlorineAmmonia

CausticFerric Sulfate, AcidPAC

Actiflo –Carb®Offsite

Storage

Polymer,

Microsand

UF

Actiflo‐Carb®, UF membrane (Additional pathogen protection)

PAC-T&O control

New site and processes-need underground utilities to and from new site. Option for redeveloping existing site for residential and/or commercial use.

23

Alternatives Capital Cost Comparison

Alternative 1 -PAC-UV

(at existing site)

Alternative 2 - IX-UF-GAC

(at existing site)


(near ECR)

Alternative 4 -Actiflo-Carb-UF

(at Riviera Beach)

Other Fees $5.6 $18.0 $61.2 $51.3

Site Property Value $0.0 $0.0 -$33.2 -$33.2

Site Works, Power, Demolition $4.3 $14.0 $76.7 $69.4

Treatment $23.6 $75.1 $96.1 $92.6

Pump Stations, Storage, Conveyance $0.0 $0.7 $161.9 $109.2

-$100

-$50

$0

$50

$100

$150

$200

$250

$300

$350

$400

$45020

18 C

AP

EX

Co

st(i

n M

illio

ns)

Other Fees

Site Property Value

Site Works, Power,Demolition

Treatment

Pump Stations, Storage,Conveyance $33.6

$107.7

$362.7

$289.3

24

Alternatives R&R Cost Comparison

Alternative 1 - PAC-UV

(at existing site)


(at existing site)


(near ECR)

Alternative 4 - Actiflo-Carb-UF

(at Riviera Beach)

Annual R&R CIP 2015-2019 $2.8 $2.3 $0.9 $0.9

Annual R&R CIP 2020-2024 $6.4 $1.7 $0.0 $0.0

Annual R&R CIP 2025-2044 Est. $4.8 $4.8 $4.8 $4.8

$0.0

$1.0

$2.0

$3.0

$4.0

$5.0

$6.0

$7.0A

nn

ual

R&

R C

ost

s(i

n M

illio

ns)

Annual R&R CIP 2015-2019

Annual R&R CIP 2020-2024

Annual R&R CIP 2025-2044 Est.

25

Alternatives Operating Cost Comparison

ExistingAlternative 1 - PAC-

UV(at existing site)


(at existing site)


(near ECR)

Alternative 4 -Actiflo-Carb-UF

(at Riviera Beach)

Other OPEX $3.91 $3.91 $3.91 $3.91 $3.91

Waste to Sewer $0.10 $0.10 $0.20 $0.19 $0.11

Sludge $0.96 $0.96 $0.00 $0.00 $0.90

Labor $4.47 $4.47 $4.19 $3.63 $3.63

Chemicals $4.38 $4.38 $2.22 $2.22 $4.24

Energy $1.40 $1.44 $1.54 $1.70 $1.83

$0.00

$2.00

$4.00

$6.00

$8.00

$10.00

$12.00

$14.00

$16.00

$18.00

2018

OP

EX

Co

st

(in

Mill

ion

s)

Other OPEX

Waste to Sewer

Sludge

Labor

Chemicals

Energy

26

Alternatives Lifecycle Cost Comparison

$0.00

$100.00

$200.00

$300.00

$400.00

$500.00

$600.00

$700.00

$800.00

$900.00

$1,000.00

0 5 10 15 20 25 30

Cu

mu

lati

ve N

et P

rese

nt

Val

ue

(201

8 M

illio

ns)

Years in Operation

Alternative 1 PAC-UV(at existing site)Alternative 2 IX-UF-GAC(at existing site)Alternative 3 IX-UF-GAC (near ECR)Alternative 4 Actiflo-Carb-UF(at Riviera Beach)Existing

27

Summary of Financing Options and Parameters for Alternatives

Not membranes!

Alternative 1 PAC-UV as it would not degrade the Utilities debt position and would not require an immediate utility rate increase.

The project team is moving ahead with the design and ground breaking for construction is expected in late spring of 2016.

28

…and the winner is?

Questions?

29

fsawwa paper and presentation integrated master planning wpb 12012015

Documents